RU2325411C2 - Method of polyolefine nanocomposite production - Google Patents

Abstract

FIELD: inorganic chemistry.

SUBSTANCE: invention refers to production of nanocomposites using olefinic polymeric matrix and smectite clay. Polyolefine nanocomposite is made by melt mixing (a) polyolefine and (b) smectite clay with at least one intercalating agent occurrence. Ratio of intercalating agent and clay is at least 1:3, assuming ash content rate of specified clay. Hydroxide-substituted esters of carboxylic acid, amides, hydroxide-substituted amides and oxidated polyolefines solid at room temperature are used as intercalating agent. Method versions enable to produce nanocomposites with improved mechanical and barrier properties and high economic indicator "cost-effectiveness".

EFFECT: production of nanocomposites with improved mechanical properties and economic indicators.

32 cl, 1 dwg, 8 tbl, 7 ex

Description

FIELD OF THE INVENTION

The present invention relates to a method for producing a nanocomposite from an olefin polymer matrix and smectite clay.

BACKGROUND OF THE INVENTION

Layered clay minerals such as montmorillonite are composed of silicate layers having a thickness in the nanometer range (1 nanometer = 10E). Dispersions of such layered materials in polymers are often called nanocomposites.

It is known that silicates such as smectite clays, for example sodium and calcium montmorillonite, can be treated with various types of swelling agents, such as organic ammonium ions, to incorporate the molecules of these swelling agents between adjacent flat silicate layers, and thereby for increase the space between these layers. Then silicates with such incorporated molecules can be delaminated, that is, the silicate layers can be separated, usually by mixing with shear. It was found that individual silicate layers, when mixed with the matrix polymer before, after, or during the polymerization of the matrix polymer, contribute to a significant improvement in one or more polymer properties, such as elastic modulus and / or thermal properties.

So, for example, in published application US 2001/0008699, which was issued US patent No. 6395386 described multilayer polymer / plate films, in which the inner layer consists of a polymer carrier and plate particles of a certain size. These plates can be made of clay and non-clay materials. Dispersing agents such as alcohols and water dispersible polymers may also be present. US 4,764,326 describes a process for blending a polyolefin before extrusion, with a process aid to facilitate extrusion and containing (a) amide acid or alkylene bis-amide, (b) an aliphatic hydrocarbon or mixtures thereof, and (c) a high density oxygen-containing ethylene polymer, such as oxidized polyethylene. Fillers may also be present, such as clay, the type of which is not specifically indicated. US Pat. No. 4,810,734 describes a method for producing composite materials by contacting a layered clay mineral such as montmorillonite with a swelling agent in the presence of a dispersion medium to form a complex; mixing said complex with a monomer; polymerizing said monomer in a mixture. Suitable dispersion media are ethanol, ethylene glycol, glycerin, a mixture of water and dimethylformamide and acetic acid.

Polyolefin nanocomposites are usually prepared using maleic anhydride grafted polyolefins, used to impart compatibility and to disperse organic clay in a polymer matrix. To achieve a high level of incorporation, a minimum grafted polymer: organic clay ratio of 5: 3 is usually required; and to separate the layers requires a ratio of 10+: 3. Since grafted copolymer and organic clay are expensive materials, the above relationships greatly affect the cost of the final product.

Therefore, it is necessary to obtain nanocomposites with improved mechanical and barrier properties and with a high economic cost-effectiveness ratio, which would serve as an alternative to existing maleic anhydride grafted polyolefins.

SUMMARY OF THE INVENTION

In accordance with the present invention, a method for producing a polyolefin nanocomposite comprises melt mixing (1) a polyolefin and (2) smectite clay in the presence of at least one intercalating agent that is solid at room temperature and which is selected from the group consisting of (a ) hydroxy substituted carboxylic acid esters, (2) amides, (3) hydroxy substituted amides and (4) oxidized polyolefins, where the ratio of intercalating agent to clay is at least 1: 3, based on sol spine of clay.

The obtained nanocomposite has an increased modulus of elasticity compared to nanocomposites obtained using polypropylene grafted with maleic anhydride as an agent that improves compatibility and dispersibility. When using the intercalating agents of the present invention, no negative effect on the strength and temperature of thermal deformation of the product was observed.

A brief description of the graphic material

The drawing shows a graph of the dependence of the modulus of elasticity in bending (MPa) and the ash content (%) of the nanocomposite obtained using untreated montmorillonite clay and montmorillonite clay, which was treated with a quaternary ammonium compound using the same intercalating agent.

DETAILED DESCRIPTION OF THE INVENTION

The polyolefin used as the matrix for the composite material of the present invention can be, for example, an ethylene homopolymer, a propylene homopolymer, an ethylene / propylene copolymer, an ethylene or propylene copolymer and a C ₄ -C ₈ alpha olefin, for example linear low density polyethylene (LLDPE) , low density polyethylene (LDPE) or ethylene / propylene rubber, provided that it does not affect the interaction of clay and the intercalating agent. The choice of the preferred polyolefin depends on the purpose of use of this product.

Smectite clay minerals are, for example, montmorillonite, nontronite, beidellite, volkonskoite, hectorite, saponite, saukonite, sobokite, stevensite and swfordford. Montmorillonite is preferred. Smectite clays have properties that differ from those of kaolin clays, which are commonly used as fillers in polymeric materials.

A smectite clay mineral can be untreated or it can be modified with an agent that causes swelling and containing organic cations by treating this clay with one or more organic cationic salts to replace the metal cations present in the space between the layers of this clay material with organic cations, and most to increase the distance between these layers. The increase in the distance between these layers of layered silicate promotes the inclusion of clay in other materials, and in this case in the olefin polymer.

Organic cationic salt swelling agents contain an onium ion and may contain a functional ion or a functional group that interacts with and binds to the polymer. Examples of the onium ion are ammonium ion (—N ₃ ⁺ ), trimethylammonium ion (—N ⁺ (CH ₃ ) ₃ ), trimethylphosphonium ion (P ⁺ (CH ₃ ) ₃ ), and dimethyl sulfonium ion (S ⁺ (CH ₃ ) ₂ ). Examples of functional groups are vinyl groups, carboxyl groups, hydroxyl groups, epoxy groups and amino groups. Organic cations can be used alone or in combination with each other. Suitable swelling agents are, for example, poly (propylene glycol) bis (2-aminopropyl ether), poly (vinylpyrrolidone), dodecylamine hydrochloride, octadecylamine hydrochloride and dodecylpyrrolidone. Clay can be swollen under the influence of water before the introduction of the Quaternary ammonium ion. Clays processed in this way are commercially available.

The third component of the composite material is at least one intercalating agent for smectite clay. The intercalating agent is solid at room temperature and is selected from the group consisting of (a) hydroxy-substituted carboxylic acid esters, such as, for example, glycerol monostearate, sorbitan monostearate and sorbitan tristearate, (b) amides, such as, for example, behenamide , stearyl stearamide and ethylene bis stearamide, (c) hydroxy substituted amides, such as, for example, ethyl alcohol, stearamide and (d) oxidized polyolefins, such as, for example, waxes based on oxidized polyethylene and wax based on an oxidized polymer polyethylene / oxidized ethylene vinyl acetate. Oxidized polyolefins contain hydroxy groups and carboxylic acid ester groups, as well as other oxygen-containing functional groups. In the present invention, hydroxy substituted amides are most suitable as intercalating agents.

The ratio "intercalating agent: smectite clay" is at least 1: 3, preferably 2: 3-4: 3, but can reach 9: 3 or higher. The amount of clay is determined by measuring the ash residue. The relationship "intercalating agent: smectite clay" depends on the particular intercalating agent and is a function of polarity and molecular weight. The more clay is used, the more intercalating agent is required.

When the intercalating agents of the present invention are added to a standard system, i.e. a system that does not contain smectite clay, some physical properties of the matrix resin or filled resin deteriorate with increasing amount of intercalating agent. Typical fillers are kaolin and CaCO ₃ . In these systems, the intercalating agent acts as a processing aid or plasticizer, i.e., the melt flow rate of the matrix resin should increase, and the elastic modulus should decrease. But this is not the case for nanocomposites made using the intercalating agents of the present invention, that is, in this case there is no negative effect on the strength of the nanocomposite and on the temperature of its thermal deformation (HDT), but the elastic modulus increases.

Composite materials are prepared by a process comprising melt mixing (1) a polyolefin and (2) smectite clay in the presence of at least one intercalating agent for the clay. The intercalating agent is solid at room temperature and is selected from the group consisting of (a) hydroxy-substituted carboxylic acid esters, (b) amides, (c) hydroxy-substituted amides and (d) oxidized polyolefins. Room temperature is 23 ° C. The ratio of intercalating agent to clay is at least 1: 3 based on the ash content of this clay. The preparation of the mixture is usually carried out in an extruder, but other methods of preparing the mixture can also be used. The mixing order of these three components does not play a decisive role.

Typical dispersing agents used for smectite clays promote the separation of silicates and the homogeneous dispersion of individual silicate layers throughout the polymer matrix. Pictures of the nanocomposites of the present invention, taken using a transmission electron microscope, showed that the clay particles were not homogeneously dispersed throughout the polymer matrix. Silicate layers were not completely separated, although the formation of large agglomerates was not observed.

These nanocomposites obtained by the method of the present invention can be used for the manufacture of industrial products by standard molding methods, such as centrifugal melt molding, injection molding, vacuum molding, sheet molding, injection molding and extrusion. Examples of such products are parts for technical equipment, for household appliances and for sports equipment, bottles, containers, components for the electrical and electronic industries, car parts and fiber. These nanocomposites are especially valuable for fabricated extruded films and film laminates, for example films used for food packaging.

The test methods used to evaluate the composites of the present invention are test methods for:

Tensile Strength ASTM D-638-89

Yield strength

Elongation at yield

Elongation at break

Bending ASTM D-790-86

Elastic modulus

Strength

ASTM D-256-87 Notched Izod Impact Strength

Ash content ASTM D-5630-01

MFR (Propylene Polymer Materials) (230 ° C, 2.16 kg) ASTM D-1258

In the present description, all parts and percentages are indicated by weight, unless otherwise specified.

Example 1

This example shows the effect that the physical properties of a nanocomposite product use of an intercalating agent instead of polypropylene grafted with maleic anhydride and used as an agent to ensure compatibility.

The compositions shown in Table 1 were prepared on a Coperion Corotation Twin Screw Extruder. Extrusion was carried out under the following conditions: temperature inside the drum = 190 ° C, revolutions per minute (rpm) = 400. All samples were obtained by injection molding in the form of samples for tensile testing according to ASTM, on a Battenfeld molding machine with mold slots 5 ounces at a drum temperature of 199 ° C (390 ° F), molding temperature of 60 ° C (140 ° F), and an injection speed of 25.4 mm / s (1 inch / s). The physical properties of each sample are presented in table 1.

In table 1, polypropylene (PP) is a homopolymer having (MFR) 4 dg / 10 min and supplied by Basell USA Inc. MA-g-PP is an Epolene E43 modified polypropylene wax having an acid number of 45, a number average molecular weight of M _n 3900, and a weight average molecular weight of M _w 9100 and supplied by Eastman Chemical Company. Organic clay is Cloisite 20A organic clay (38% organic matter, 62% montmorillonite), i.e., natural montmorillonite clay modified with di (solid fat) di (methyl) quaternary ammonium chloride salt, supplied by Southern Clay Products Inc. The Fiberstab 210 stabilizer was a mixture of 50% hydroxylamine FS-042 and 50% sterile hindered amine Chimassorb 119, and was purchased from Ciba Specialty Chemicals Corporation. The intercalating agent is Adawax 280 Ethylene Bis Stearamide (EBS), and was purchased from Rohm & Haas.

Table 1 Sample No. Control 1 Control 2 one 2 3 four 5 6 PP (%) one hundred 91.80 95.80 94.80 93.80 92.80 87.80 87.80 MA-g-PP (%) 5.00 5.00 7.00 EBS (%) 1.00 2.00 3.00 4.00 4.00 2.00 Organic clay (%) 3.00 3.00 3.00 3.00 3.00 3.00 3.00 Stabilizer (%) 0.20 0.02 0.20 0.20 0.20 0.20 0.20 MFR at 2.16 kg (dg / 10 min) 4.0 4.4 4.4 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 5.25 36.3 / 526 35.8 / 5.19 36.1 / 5.24 35.6 / 5.16 36.1 / 523 34.4 / 4.99 35.5 / 5.15 Elongation at yield (%) 11.3 9.6 8.6 7.8 7.3 7.3 7.2 7.5 Elongation at break (%) 40 92 79 106 131 111 69 89 Bend Strength (MPa / Kilo-psi) 47.7 / 6.92 48.9 / 7.09 50.3 / 7.30 50.8 / 7.37 50.6 / 7.35 51.3 / 7.44 49.4 / 7.16 50.6 / 7.34 Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1586/230 1662/241 1724/250 1779/258 1772/257 1696/246 1696/246 The increase in the elastic modulus - 7 13 17 21 twenty fifteen fifteen Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 32.0 (0.6) 37.4 (0.7) 48.0 (0.9) 64.1 (12) 58.7 (1.1) 42.7 (0.8) 37.4 (0.7) Ash content (%) 0 1,57 1.84 1.85 1.83 1.83 1.80 1.86

Table 1 shows the physical properties of the samples obtained with and without the use of MA-g-PP and using various amounts of EBS. These data showed that the notched Izod impact strength increased, and that when using EBS, the increase in elastic modulus was much higher than when using MA-g-PP even at lower levels of EBS. These beneficial effects occurred even when the MFR of sample 3 did not change compared to the MFR of the resin. An increase in the elastic modulus with a constant MFR was significant, which indicated that EBS did not act as a plasticizer (giving lower elastic moduli and an increase in the melt flow rate). On the contrary, these data indicate that the use of EBS allows a significant level of clay incorporation to be achieved. This conclusion was confirmed by microscopic examination.

When combining EBS with MA-g-PP (samples 5 and 6 in table 1), physical properties indicated the absence of synergism. Indeed, the addition of MA-g-PP degraded the properties of the material compared to the properties of materials obtained using only EBS. For example, sample 5 had a lower modulus of elasticity, lower strength, and lower notched Izod impact strength than sample 4.

Example 2

This example shows the effect that the physical properties of a nanocomposite product have on the use of glycerol monostearate (GMS) as an intercalating agent in the presence or absence of MA-g-PP.

All samples were injection molded to obtain ASTM standard tensile test samples as described in Example 1. The physical properties of each sample are shown in Table 2.

PP, MA-g-PP, organic clay and stabilizer were the same as in example 1.

table 2 Sample No. Control 1 Control 2 one 2 PP (%) one hundred 91.80 95.80 94.80 MA-g-PP (%) 5.00 GMS (%) 1.00 2.00 Organic clay (%) 3.00 3.00 3.00 Stabilizer (%) 0.20 0-20 020 MFR at 2.16 kg (dg / 10 min) 4.0 4.4 4.0 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 525 36.3 / 5.26 36.2 / 525 36.3 / 526 Elongation at yield (%) 11.3 9.6 9.1 8.9 Elongation at break (%) 40 92 107 103 Bend Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1586/230 1703/247 1655/240 Strength (MPa / Kilo-psi) 47.7 / 6.92 48.9 / 7.09 49.8 / 7.23 49.9 / 724 The increase in the modulus of elasticity (%) - 7 fifteen 12 Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 32.0 (0.6) 37.4 (0.7) 42.7 (0.8) Ash content (%) 0 1,57 1.83 1.83 PP (%) 93.80 92.80 87.80 87.80 MA-g-PP (%) 5.00 7.00 GMS (%) 3.00 4.00 4.00 2.00 Organic clay (%) 3.00 3.00 3.00 3.00 Stabilizer (%) 0.20 0.20 0.20 0.20 MFR at 2.16 kg (dg / 10 min) Tensile strength Yield Strength (MPa / Kilo-psi) 35.3 / 5.12 34.5 / 5.00 34.1 / 4.94 35.6 / 5.16 Elongation at yield (%) 8.9 8.7 9.6 9.1 Elongation at break (%) 126 104 120 64 Bend Modulus of Elasticity (MPa / Kilo-psi) 1661/241 1641/238 1489/216 1572/228 Strength (MPa / Kilo-psi) 47.8 / 6.94 46.9 / 6.80 45.0 / 6.53 48.0 / 6.96 The increase in the modulus of elasticity (%) 13 eleven one 7 Notched Izod Impact Strength [J / m (lb · ft / in)] 53.4 (1.0) 53.4 (1.0) 37.4 (0.7) 26.7 (0.5) Ash content (%) 1.85 1.97 2.08 2.19

All data for the modulus of elasticity presented in Table 3 and obtained for samples containing GMS, used only as a functionalized additive (samples 1-4), were better than the data for a sample containing MA-g-PP, used only as functionalized additives (control 2). Better results were also obtained for notched Izod impact strength. These data showed that the combination of GMS and MA-g-PP (samples 5 and 6) gave worse results than samples with only one GMS.

Example 3

This example illustrates a comparison of the physical properties of nanocomposites obtained using equal amounts of three amide intercalating agents with the physical properties of nanocomposites obtained using MA-g-PP, but without the use of an intercalating agent.

All samples were mixed and molded by injection molding to obtain standard samples for tensile testing according to ASTM, as described in example 1. The physical properties of each sample are presented in table 3.

PP, MA-g-PP, organic clay and stabilizer were the same as in Example 1. Saturated fatty acid amide, kemamide B was obtained from a mixture of arachidonic and behenic acids. The secondary amide, Kemamide S-180, is a substituted fatty acid amide derived from stearic acid and stearylamine. Both of these amides are available from Crompton Corporation.

Table 3 Sample No. Control 1 Control 2 one 2 3 PP (%) one hundred 91.80 194.80 94.80 94.80 MA-g-PP (%) 5.00 Kemamide B (%) 2.00 Kemamide S180 (%) 2.00 EBS (%) 2.00 Organic clay (%) 3.00 3.00 3.00 3.00 Stabilizer (%) 0.20 0.20 0.20 0.20 MFR at 2.16 kg (dg / 10 min) 4.0 5.2 4.6 4.8 4.6 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 5.25 35.4 / 5.14 34.5 / 5.01 34.1 / 4.95 34.9 / 5.06 Elongation at yield (%) 11.3 9.3 8.8 8.9 7.8 Elongation at break (%) 40 72 95 81 98 Bend Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1544/224 1613/234 1579/229 1689/245 Strength (MPa / kilo-pound per square inch), 47.7 / 6.92 47.8 / 6.94 47.6 / 6.91 47.1 / 6.83 49.1 / 7.12 The increase in the modulus of elasticity (%) - 5 9 7 fourteen Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 32.0 (0.6) 37.4 (0.7) 37.4 (0.7) 48.0 (0.9) Ash content (%) 0 1.94 1.77 1.78 1.80

Sample 3 containing EBS as an intercalating agent had the highest increase in elastic modulus, and all amide intercalating agents gave a larger increase in elastic modulus than control 2.

Example 4

This example shows the effect of intercalating agents of some other types on the physical properties of the samples.

All samples were mixed and molded by injection molding to obtain ASTM standard tensile test samples as described in Example 1. The physical properties of these samples are shown in Tables 4 and 5.

PP, MA-g-PP, organic clay and stabilizer were the same as in Example 1. STS is sorbitan tristearate, Glycomul TSK, supplied by Lonza Inc. Lonzest SMS Sorbitan Monostearate is supplied by Lonza Inc. Abriflo 65 Stearamide Ethyl Alcohol is supplied by Abril Industrial Waxes Ltd. Paracine Hydroxyamide 220 and Paricin 285 Hydroxyamide are aliphatic hydroxyamides supplied by CasChem Inc.

Table 4 Sample No. Control 1 Control 2 one 2 3 PP (%) one hundred 91.8 94.80 94.80 94.80 MA-g-PP (%) 5.00 GMS (%) 2.00 STS (%) 2.00 SMS (%) 2.00 Organic clay (%) 3.00 3.00 3.00 3.00 Stabilizer (%) 0.20 0.20 0.20 0.20 MFR at 2.16 kg (dg / 10 min) 4.0 5.2 5,0 5.3 5.1 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 5.25 35.4 / 5.14 34.3 / 4.98 34.7 / 5.03 34.7 / 5.03 Elongation at yield (%) 11.3 9.3 9.1 9.1 7.8 Elongation at break (%) 40 72 135 104 130 Bend Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1544/224 1641/238 1613/234 1744/253 Strength (MPa / Kilo-psi) 47.7 / 6.92 34.5 / 6.94 47.5 / 6.89 48.0 / 6.96 49.8 / 7.23 The increase in the modulus of elasticity (%) - 5 eleven 9 eighteen Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 32.0 (0.6) 37.4 (0.7) 37.4 (0.7) 37.4 (0.7) Ash content (%) 0 1.94 1.76 1.81 1.80

Table 5 Sample No. Control 1 Control 2 one 2 3 PP (%) one hundred 91.80 94.80 94.80 94.80 MA-g-PP (%) 5.00 Paricin 285 (%) 2.00 Paricin 220 (%) 2.00 Abbriflo 65 2.00 Organic clay (%) 3.00 3.00 3.00 3.00 Stabilizer (%) 0.20 0.20 020 0.20 MFR at 2.16 kg 5.2 5.3 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 525 35.4 / 5.14 36.5 / 5.29 35.9 / 5.20 34.7 / 5.04 Elongation at yield (%) 11.3 9.3 7.7 7.7 8.7 Elongation at break (%) 40 72 one hundred 120 89 Bend Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1544/224 1813/263 1862/270 1675/243 Strength (MPa / Kilo-psi) 47.7 / 6.92 47.8 / 6.94 52.5 / 7.61 52.5 / 7.61 48.1 / 6.97 The increase in the modulus of elasticity (%) - 5 23 26 fourteen Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 32.0 (0.6) 48.0 (0.9) 53.4 (1.0) 37.4 (0.7) Ash content (%) 0 1.94 1.96 1.86 1.90

The data obtained showed that both Paracin products gave the same increase in elastic modulus as EBS. All samples obtained using intercalating agents had higher elastic moduli than control 2.

Example 5

This example shows the effect of intercalating agents such as oxidized polyethylene on the physical properties of samples.

All samples were mixed and molded by injection molding to obtain standard samples for tensile testing according to ASTM, as described in example 1. The physical properties of these samples are shown in table 6.

PP, MA-g-PP, organic clay and stabilizer were the same as in example 1. The oxidized PE wax AC 656 had a dropping point of 98 ° C, a viscosity (cP) of 185 at 140 ° C, and an acid number of 15. Oxidized HDPE wax AC 395 had a dropping temperature of 137 ° C, a viscosity of 2500 at 150 ° C and an acid number of 41. The oxidized HDPE wax AC 316 had a dropping temperature of 140 ° C, a viscosity of 8500 at 150 ° C and an acid number of 16. AC 645 represents a wax based on a copolymer of oxidized PE / oxidized EVA (<30% /> 70%). All of these components were purchased from Honeywell.

Table 6 Sample No. Control 1 Control 2 one 2 3 four PP (%) one hundred 91.8 94.80 94.80 94.80 94.80 MA-g-PP (%) 5.00 AC 656 (%) 2.00 AC 645 (%) 2.00 AC 395 (%) 2.00 AC 316 (%) 2.00 Organic clay (%) 3.00 3.00 3.00 3.00 3.00 Stabilizer (%) 0.2 0.20 0.20 0.20 0.20 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 5.25 35.5 / 5.14 34.3 / 4.97 34.9 / 5.06 35.3 / 5.12 35.6 / 5.17 Elongation at break (%) 40 72 one hundred 120 110 120 Elongation at yield (%) 11.3 9.3 9.8 9.5 9.0 9.0 Bend Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1544/224 1544/224 1648/239 1703/247 1724/250 Strength (MPa / Kilo-psi) 47.7 / 6.92 47.8 / 6.94 46.7 / 6.78 49.1 / 7.12 50.5 / 733 50.7 / 7.35 The increase in the modulus of elasticity (%) - 5 5 12 fifteen 17 Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 32.0 (0.6) 32.0 (0.6) 37.4 (0.7) 37.4 (0.7) 37.4 (0.7) Ash content (%) 0 1.94 1.74 1.78 1.76 1.78

Example 6

This example illustrates a comparison of the physical properties of nanocomposites made using clay treated with a quaternary ammonium compound, unmodified clay, and the same intercalating agent.

These samples were mixed and formed to obtain ASTM standard tensile test samples as described in Example 1. The physical properties of each sample are shown in Table 7. The PP, stabilizer, organic clay, and EBS were the same as those in Example 1. Unmodified Refined Montmorillonite Clay Nanocor PGW was purchased from Nanocor Inc.

Table 7 Sample No. The control one 2 PP (%) one hundred 94.80 94.80 EBS (%) 2.00 3.00 Organic clay (%) 3.00 Nanocor PGW (%) 2.00 Stabilizer (%) 0.20 0.20 Tensile strength Yield Strength (MPa / Kilo-psi) 36.2 / 5.25 35.4 / 5.14 34.7 / 5.03 Elongation at yield (%) 11.3 7.7 9.0 Elongation at break (%) 40 123 85 Bend Strength (MPa / Kilo-psi) 47.7 / 6.92 51.4 / 7.46 492 / 7.13 Modulus of Elasticity (MPa / Kilo-psi) 1475/214 1806/262 1682/244 Notched Izod Impact Strength [J / m (lb · ft / in)] 26.7 (0.5) 58.7 (1.1) 58.7 (1.1) Ash content (%) 0 1.79 1.18

A graphic comparison of the properties of processed and unprocessed clays is presented in the drawing. The linear dependence of the elastic moduli of the resin, untreated clay and organic clay is shown. The increase in elastic modulus for untreated clay with EBS was the same as the increase in modulus for organic clay with EBS based on the ash content despite a coarser dispersion of untreated clay as determined by optical microscopy.

Example 7

This example illustrates the change in the physical properties of the nanocomposite obtained on the basis of linear low density polyethylene (LLDPE) using SMS as an intercalating agent.

The compositions shown in table 8 were obtained on a Coperion corotation twin-screw extruder 40 mm at a temperature inside the drum of 200 ° C and at 600 rpm. The samples were ASTM standard tensile test specimens formed by injection molding on a Battenfeld molding machine with 5 ounce mold slots at a drum temperature of 177 ° C (350 ° F) and a molding temperature of 32 ° C (90 ° F) and at an injection speed of 12.7 mm / s (0.5 in / s). The physical properties of each sample are presented in table 8.

The organic clay and stabilizer were the same as in Example 1. LLDPE contained propylene and butene-1 as comonomers and was purchased from Daelim Industrial Co., Ltd. SMS is described in Example 4. The ethylene / maleic anhydride copolymer AC 575 was purchased from Honeywell.

Table 8 Sample No. Control 1 Control 2 Control 3 one LLDPE (%) one hundred 95.80 91.8 91.80 AC 575 4.00 SMS (%) 4.00 Organic clay (%) 4.00 4.00 4.00 Stabilizer (%) 0.20% 0.20 0.20 Tensile strength Maximum Strength (MPa / Kilo-psi) 15.6 / 2.26 13.6 / 1.97 15.1 / 2.20 14.5 / 2.10 Elongation at break (%) 500+ 450 500+ 500+ Bend Modulus of Elasticity (MPa / Kilo-psi) 282 / 40.9 323 / 46.8 322 / 46.7 324 / 47.0 Strength (MPa / Kilo-psi) 10.7 / 1.55 11.7 / 1.70 12.1 / 1.75 11.7 / 1.69 The increase in the modulus of elasticity (%) - fourteen fourteen fifteen Ash content (%) - 2.22 2,39 2.42

The data obtained showed that when using sorbitan monostearate as an intercalating agent, the nanocomposite product had an increased modulus of elasticity, but there was no negative effect on the strength of the product. As can be seen in the picture taken with an optical microscope in a transmitted light beam, the optical dispersion of clay particles in sample 1 was better than that of control samples 2 and 3 with similar physical properties. This property should be taken into account in those applications where the appearance of the product is important, for example, in the manufacture of films.

Other features, advantages, and embodiments of the invention will be apparent to those skilled in the art based on the foregoing description of the invention. Therefore, although the present invention is described above with specific examples of its implementation, various changes and modifications can be made to it, without departing from the essence and scope of the invention as set forth in the following claims.

Claims (32)

1. A method of producing a polyolefin nanocomposite, comprising melt mixing (a) a polyolefin and (b) smectite clay in the presence of at least one intercalating agent that is solid at room temperature and which is selected from the group consisting of (i) hydroxy-substituted amides and (ii) oxidized polyolefins, where the ratio of intercalating agent to clay is at least 1: 3 based on the ash content of said clay. 2. The method according to claim 1, where the polyolefin (a) is a propylene homopolymer. 3. The method according to claim 1, where the polyolefin (a) is an ethylene homopolymer. 4. The method according to claim 1, where the polyolefin (a) is a copolymer of ethylene and a C ₄ -C ₈ -α-olefin. 5. The method according to claim 1, where the smectite clay is montmorillonite. 6. The method according to claim 1, where the intercalating agent is a hydroxy-substituted amide. 7. The method according to claim 6, where the intercalating agent is ethyl alcohol stearamide. 8. The method according to claim 1, where the intercalating agent is an oxidized polyolefin. 9. The method of claim 8, where the oxidized polyolefin is wax based on oxidized polyethylene. 10. The method of claim 8, where the oxidized polyolefin is a wax based on an oxidized polyethylene / polyvinyl acetate polymer. 11. A method of producing a polyolefin nanocomposite, comprising melt mixing (a) a polyolefin and (b) smectite clay in the presence of at least one intercalating agent that is solid at room temperature and which is selected from the group consisting of (i) hydroxy-substituted carboxylic acid esters and (ii) amides, wherein the ratio of intercalating agent to clay is at least 1: 3 based on the ash content of said clay. 12. The method according to claim 11, where the polyolefin (a) is a propylene homopolymer. 13. The method according to claim 11, where the polyolefin (a) is an ethylene homopolymer. 14. The method according to claim 11, where the polyolefin (a) is a copolymer of ethylene and a C ₄ -C ₈ -α-olefin. 15. The method according to claim 11, where the smectite clay is montmorillonite. 16. The method according to claim 11, where the intercalating agent is a hydroxy-substituted carboxylic acid ester. 17. The method according to clause 16, where the hydroxy-substituted carboxylic acid ester is sorbitan monostearate. 18. The method according to clause 16, where the hydroxy-substituted carboxylic acid ester is glycerol monostearate. 19. The method according to clause 16, where the hydroxy-substituted carboxylic acid ester is sorbitan tristearate. 20. The method according to claim 11, where the intercalating agent is an amide. 21. The method according to claim 20, where the intercalating agent is ethylene bis stearamide. 22. A method for producing a polyolefin nanocomposite, consisting essentially of melt-mixing (a) a polyolefin and (b) smectite clay in the presence of at least one intercalating agent that is solid at room temperature and which is selected from the group consisting of (i) hydroxy substituted carboxylic acid esters; and (ii) amides, wherein the ratio of intercalating agent to clay is at least 1: 3 based on the ash content of said clay. 23. The method according to item 22, where the polyolefin (a) is a propylene homopolymer. 24. The method according to item 22, where the polyolefin (a) is an ethylene homopolymer. 25. The method according to item 22, where the polyolefin (a) is a copolymer of ethylene and a C ₄ -C ₈ -α-olefin. 26. The method according A.25, where smectite clay is montmorillonite. 27. The method according to item 22, where the intercalating agent is a hydroxy-substituted carboxylic acid ester. 28. The method according to item 27, where the hydroxy-substituted carboxylic acid ester is sorbitan monostearate. 29. The method of claim 27, wherein the hydroxy substituted carboxylic acid ester is glycerol monostearate. 30. The method according to item 27, where the hydroxy-substituted carboxylic acid ester is sorbitan tristearate. 31. The method according to item 22, where the intercalating agent is an amide. 32. The method according to p, where the intercalating agent is ethylene bis-stearamide.

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